Engine coolant conduit with integral alternator and exhaust gas recirculation valve

ABSTRACT

In a preferred embodiment, an engine coolant crossover assembly includes a crossover conduit member carrying an integral liquid cooled alternator and liquid cooled exhaust gas recirculation valve. The integration of one or both of these parts into the coolant crossover eliminates many parts from the total assembly. These parts include; attachment brackets, coolant hoses, hose clamps, cast mounting blocks, coolant tubes and attachment bolts. Reduction of these parts reduces system costs, assembly time, mass and potential coolant leak paths. A temperature sensor and a thermostat housing may also be included in the crossover assembly. The assembly may also be made part of an intake manifold for an integrated air fuel module of a V-type engine.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 60/149,141, filed Aug. 16, 1999.

TECHNICAL FIELD

This invention relates to engine cooling and to cooling of engineaccessories mounted within a conduit member such as a coolant crossovermember.

BACKGROUND OF THE INVENTION

Increased use of electronics and electrical devices on automobiles hasincreased the load on charging systems and driven a need for moreefficient higher output alternators. A method used to increase theefficiency of the alternators is to liquid cool them rather than thetraditional air-cooling. These liquid cooled alternators use the enginecoolant, routed through the outer housing of the unit, to cool theelectronics and allow more efficient internal geometry. Normally thealternator is bracket mounted to the front of the engine and the coolantis routed to the alternator via a flexible line secured by clamps. Asecond set of hoses and clamps then routes the coolant from thealternator back to the engine coolant system.

Exhaust gas recirculation valves (EGR) also need to be liquid cooled toimprove their performance and extend their usable life. Traditionallyengine coolant is passed through an EGR valve mounting block orpedestal. The EGR is an emissions control device that admits exhaust gasinto the inlet air of the engine. This exhaust gas is allowed into theintake air during certain engine operating conditions and is used tocontrol the tail pipe emissions of the engine. The high temperature ofthe exhaust gas, that the valve controls, drives the need for valvecooling.

A coolant crossover, traditionally used on a V style internal combustionengine, carries the engine coolant from one bank of the engine to theopposite bank as part of the engine coolant circuit. This coolantcrossover is commonly part of the intake manifold, or can be a separatestand-alone part, and frequently contains the housing for the coolantthermostat and provisions to mount the coolant temperature-sending unit.

SUMMARY OF THE INVENTION

The present invention provides an external coolant conduit member suchas an engine coolant crossover, intake manifold or other conduit membermountable between engine components, such as cylinder heads, in acoolant circuit of an engine. The conduit member includes a bodydefining a coolant passage extending between an inlet and an outlet tothe passage. A first mount is provided for mounting in the body anelectrical generating device, such as an alternator, in heattransmitting relation to the coolant passage between the inlet andoutlet. A second mount may be provided for mounting a second engineaccessory, such as an EGR valve, in heat transmitting relation to thecoolant passage between the inlet and outlet.

The invention also provides an external coolant conduit assembly havinga conduit member, such as a coolant crossover optionally integrated witha manifold. The assembly includes an alternator, or other electricalgenerating device, and an EGR valve, or other engine accessory, mountedin the conduit member in heat transmitting relation to a coolant passagetherein for cooling the integrated elements. The assembly may alsoinclude features such as a mounting for a thermostat and a coolanttemperature sensor mounted in the conduit member and extending into thecoolant passage.

The integration of these features to a coolant crossover eliminates manyparts from the total engine assembly. These parts include; attachmentbrackets, coolant hoses, hose clamps, cast mounting blocks, coolanttubes and attachment bolts. Reduction of these parts reduces systemcosts, reduces system assembly time, reduces vehicle mass and eliminatesmany potential coolant leak paths.

These and other features and advantages of the invention will be morefully understood from the following description of certain specificembodiments of the invention taken together with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a pictorial view of a coolant crossover assembly withintegrated alternator, EGR valve and other elements according to theinvention;

FIG. 2 is a cross-sectional view of the coolant crossover showing theinternal coolant passage and some of the components mounted in thecrossover; and

FIG. 3 is a pictorial view showing a coolant crossover as in FIG. 1integrated into an intake manifold of an integrated air fuel module formounting on a V-8 engine.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In a preferred embodiment, the invention provides an engine coolantcrossover with an integral liquid cooled alternator and cooled exhaustgas recirculation valve. The integration of one or both of these partsto the coolant crossover eliminates many parts from the total assembly.These parts include; attachment brackets, coolant hoses, hose clamps,cast mounting blocks, coolant tubes and attachment bolts. Reduction ofthese parts reduces system costs, assembly time, mass and potentialcoolant leak paths.

Referring first to FIG. 1 of the drawings in detail, numeral 10generally indicates a coolant crossover assembly for use with a V-typeengine. The assembly is intended for mounting on the cylinder heads ofthe engine or on coolant passage defining portions of a cylinder block,not shown. Crossover assembly 10 includes a conduit or crossover memberhaving a body 12 in which are preferably mounted an alternator 14, anexhaust gas recirculation (EGR) valve 16, a coolant temperature sensor18 and a thermostat, not shown, mounted in a housing 20 of the body 12.A thermostat cover 22 mounts on the housing 20 and retains thethermostat in its operating position in the housing. A pulley 23 ismounted on the front of the alternator for driving the alternator by adrive belt from an associated engine, not shown.

Referring now to FIG. 2, the conduit member or body 12 defines aninternal coolant passage 24 having a coolant inlet 26 at one end and acoolant outlet 28 at the other end, at the bottom of the thermostathousing 20. A second outlet 30 is provided at the top of housing 20 forcoolant directed by the thermostat through the cover 22 to the coolantradiator, not shown. The coolant temperature sensor 18 is mounted in thebody 12 next to the thermostat housing 20 and extends into the coolantpassage 24 for sensing the coolant temperature passing out of theengine.

The inlet end of the crossover member body 12, defines a mount 32 inwhich the EGR valve 16 is received with a valve body 34 extending into arecess of the mount. An inlet port 36 connects the EGR valve body 34with a source, not shown, of engine exhaust gas. An outlet port 38connects the valve body 34 with a conduit 40 leading to an enginemanifold intake passage, not shown. A thin wall portion 41 of the mount32 places the EGR valve body 34 in heat transmitting relation with thecoolant passage 24 for carrying heat from the EGR valve to coolant inthe passage. The heat rejection may be increased by providing a branchpassage 42 for coolant flow, wherein passage 42 at least partiallysurrounds the EGR valve body 34.

Between the passage inlet 26 and outlet 28, the crossover member 12includes an enlarged opening 44 defined by an inner wall 45 having aplurality of mounting ears 46. An outer wall 48 is spaced outward of theinner wall and forms semicircular flow paths in the passage 24 carryingcoolant around the inner wall 45. The inner wall with the mounting ears46 forms a mount for the electrical alternator 14, which is received inheat exchange relation with the coolant passage 24 through the innerwall 45. Cooling fins 50 may be provided on the inner wall 45 forincreasing heat transfer from the inner wall to the coolant. Preferably,the inner and outer walls 45, 48 form the outer walls of the liquidcooled alternator 14 integrated into the coolant crossover 12. However,the alternator could be provided with a separate outer wall (not shown),which is mounted in the opening 44 for cooling the alternator.

In use, the crossover member 12 is preferably mounted on oppositecylinder heads, or on other members, of a V-type engine with the inlet26 connected with a port in one cylinder head and the outlet 28connected with a port in the other cylinder head. Within the crossover12, the coolant flows from inlet 26 to the EGR valve mount 32 withportion 41 and passage 42. Coolant then passes around the alternatoropening 44 and across fins 50 between inner and outer walls 45, 48. Thecoolant then reaches the temperature sensor 18 and continues to thethermostat housing 20, where it is directed to a radiator bypass throughoutlet 28 or to the radiator through outlet 30 for cooling of the heatedcoolant. The crossover member body 12 is made of a suitable thermallyconductive material so that the heat of exhaust gases in the EGR valveand the heat produced by the alternator in operation is conductedthrough the body 12 to the coolant in the passages 24, 42.

FIG. 3 shows an alternative embodiment of coolant crossover assembly 52with integrated liquid cooled alternator 14 and liquid cooled exhaustgas recirculation (EGR) valve 16. The liquid cooled alternator 14 isintegrated with a coolant crossover 54 that is part of the intakemanifold 56 for an integrated air fuel module 58 of a typical V-typeinternal combustion engine, not shown. The internal geometry of thecoolant passage 24 and mounting of the alternator are similar to thoseshown in FIGS. 1 and 2 previously described. In like fashion an exhaustgas recirculation valve 16 is also integrated into the coolant crossover54 of the intake manifold 56 and is cooled by the engine coolant viapassages in the crossover. Exhaust gas from the EGR valve is dischargedthrough the conduit 40 into the manifold 56.

While the invention has been described by reference to certain preferredembodiments, it should be understood that numerous changes could be madewithin the spirit and scope of the inventive concepts described.Accordingly, it is intended that the invention not be limited to thedisclosed embodiments, but that it have the full scope permitted by thelanguage of the following claims.

1. An external coolant conduit coolant assembly (10) for connectionbetween engine components in a coolant circuit of an engine, saidcoolant conduit assembly (10) comprising: a conduit member (12)mountable with said components and defining a coolant passage (24)extending between an inlet (26) and an outlet (28) in the conduit member(12); an electrical generating device (14) mounted with the conduitmember (12) in heat transmitting relation to the coolant passage (24)intermediate the inlet (26) and outlet (28); and a second heattransmitting engine accessory (16) mounted in the conduit member (12) inheat transmitting relation to the coolant passage (24) intermediate theinlet (26) and outlet (28), wherein said conduit member (12) is acrossover for connection between coolant passages in opposite banks of aV-type engine, said crossover also defining a thermostat housing (20) inthe coolant passage.
 2. An assembly as in claim 1 further comprising acoolant temperature sensor (18) mounted to said crossover and extendinginto the coolant passage.